,exchange with organisms and environment
-to survive
, organisms transfer material between the internal & external environments
↳ takes
place at exchange surfaces , always involving crossing cell plasma membranes
tissue gloid environment around cells of
multicellular organisms
majority of cells toofar away from exchange surfaces for diffusion alone to supply/ Tissue
·
remove
gloid w/ materials needed to Keep composition relatively constant
various
·
instead , absorbed materials rapidly distributed to tissue fluid & waste returned to exchange
once ,
surface for
I mass transport
removal
system maintains diffusion gradients that bring
materials toA cellsurface membranes
from
-size & metabolic rate affect amount of each material that is exchanged
m
EG
organisms
w/ high metabolic rate exchange
:
materials need larger SAivol more
-
.
reflected type of exchange surface & transport system that evolved to meet
·
in
requirements each organism of
I
exchange of respiratory gases (O2 CO2
minerals)changedeither energydiffusion
=
,
nutrients (glucose gutty acids , ,
amino acids vitamins
, ,
c
,
etc
excretory products Curea CO2 Active metabolic energy AT
·
>
,
Surface Area Volume
:
-materials absorbed used by cells that mostly make up
volume need PSA for
I
effective exchange
-small organisms SAi vol ratio .
as becomes larger at jaster rate than surface
,
vol .
increases area
I
simple diffusion only on outer surfaces
I
can
only meet needs of relatively inactive organisms
↳
cannot directly reach internal
organs
-
as a result adapted
, organisms
·
glattened shape cell too CEG flatworm
:
leaf)
so no
gar from surface ,
specialised exchange wl large ↑SA vol (Ebilungs gills
· :
areas
surfaces
.
,
Features Specialised Exchange Surfaces SAX
difference in conc.
of
-
large SA vol
:
.
=
Prate
of exchange diffusion &
length of diffusion path
-selectively permeable allow selected materials to
=
cross
-
thin short diffusion distance- easily damageddehydrated so located inside body
transportenvironmentalMediummaintain dusingradiente diprion gradient
-
movement
-
Adaptations to Maintain Temperature & Water
Cold environment Theat loss behavioural: eat like nuts /seeds, hibernate
energy goods
-
-
or
may
>
-
physical :
streamlined compact ,
body possibly v/fur insulation
,
desert-overheatingbehariwalspendlotte i water
-
Hot be is
nacan
/ mug
-
Hot/dy desert-water lossbehavioural may be nocturnal :
physical Kidneys produce less >
- :
urine to compensate for water loss in evaporation
, gas exchange in unicellular organisms and insects
Gas Exchange in Unicellular Organisms
-large SAivol .
=
oxygen
absorbed & CO2 excreted by diffusion across body surface only covered by cell-surface
membrane
to
-for digion be effective needs short pathways
,
-
limits size
of
insects
Gas Exchange Insects
in
-
Trachae microscopic network of air-filled tubes
supportedbystrengthenedringtopreventcollapsing roughout all body tissues e
of
insect & penetrate into
individual body cells
diffusion distance
↳ thin walls
short =
highly branched SA
-
gasentersleavestrachethoughpopnexokdetoncalledspiradeson
a
-
-respiratory gases in & out tracheal system in 3
ways
:
move
of
1. )longdifferingradient when cells respire oxygen used up A concentration towards ends of tracheoles
,
creates diffusion gradient to diguse to cells
from atmosphere
·
causing gaseous oxygen ,
CO2 produced by cells respiration in
dision gradient opposite direction causing gaseous CO2 to diffuse from cells to atmosphere
·
in
,
quicker digusion than water
↳
in air
Matt
traction trachea
2 enabling movements
muscles in insects mass in & out
of can
squeeze ,
of air
edu/water Fanaerobic respiration produces lactate (soluble t Doy muscle cells) ,
so water moves in
by osmosis
Spirade ·
water in ends
of
tracheoest in vol., drawing air into them so final diffusion pathway in
gas phase
trachea
↳
also leads to more water evaporation Though ,
trachees
musclegibre
Limiting Water Loss
-interrestrial organisms features that make good gas exchange system that water loss must balance without
same
I
compromising efficiency
increase
air at % saturated /water
gas exchange surface approx
IOO F
.
vapour evaporation of
less water
1. )
Small SA Vol . minimise
:
area over which water lost
is
2 ) Water
.
prod Coverings over Body Surfaces rigid I
outer skeleton of
chitin covered in waterproo cutide
.) Spiracles
3 be closed when at rest
I
can
, typically as needed
for
Oz
-to survive
, organisms transfer material between the internal & external environments
↳ takes
place at exchange surfaces , always involving crossing cell plasma membranes
tissue gloid environment around cells of
multicellular organisms
majority of cells toofar away from exchange surfaces for diffusion alone to supply/ Tissue
·
remove
gloid w/ materials needed to Keep composition relatively constant
various
·
instead , absorbed materials rapidly distributed to tissue fluid & waste returned to exchange
once ,
surface for
I mass transport
removal
system maintains diffusion gradients that bring
materials toA cellsurface membranes
from
-size & metabolic rate affect amount of each material that is exchanged
m
EG
organisms
w/ high metabolic rate exchange
:
materials need larger SAivol more
-
.
reflected type of exchange surface & transport system that evolved to meet
·
in
requirements each organism of
I
exchange of respiratory gases (O2 CO2
minerals)changedeither energydiffusion
=
,
nutrients (glucose gutty acids , ,
amino acids vitamins
, ,
c
,
etc
excretory products Curea CO2 Active metabolic energy AT
·
>
,
Surface Area Volume
:
-materials absorbed used by cells that mostly make up
volume need PSA for
I
effective exchange
-small organisms SAi vol ratio .
as becomes larger at jaster rate than surface
,
vol .
increases area
I
simple diffusion only on outer surfaces
I
can
only meet needs of relatively inactive organisms
↳
cannot directly reach internal
organs
-
as a result adapted
, organisms
·
glattened shape cell too CEG flatworm
:
leaf)
so no
gar from surface ,
specialised exchange wl large ↑SA vol (Ebilungs gills
· :
areas
surfaces
.
,
Features Specialised Exchange Surfaces SAX
difference in conc.
of
-
large SA vol
:
.
=
Prate
of exchange diffusion &
length of diffusion path
-selectively permeable allow selected materials to
=
cross
-
thin short diffusion distance- easily damageddehydrated so located inside body
transportenvironmentalMediummaintain dusingradiente diprion gradient
-
movement
-
Adaptations to Maintain Temperature & Water
Cold environment Theat loss behavioural: eat like nuts /seeds, hibernate
energy goods
-
-
or
may
>
-
physical :
streamlined compact ,
body possibly v/fur insulation
,
desert-overheatingbehariwalspendlotte i water
-
Hot be is
nacan
/ mug
-
Hot/dy desert-water lossbehavioural may be nocturnal :
physical Kidneys produce less >
- :
urine to compensate for water loss in evaporation
, gas exchange in unicellular organisms and insects
Gas Exchange in Unicellular Organisms
-large SAivol .
=
oxygen
absorbed & CO2 excreted by diffusion across body surface only covered by cell-surface
membrane
to
-for digion be effective needs short pathways
,
-
limits size
of
insects
Gas Exchange Insects
in
-
Trachae microscopic network of air-filled tubes
supportedbystrengthenedringtopreventcollapsing roughout all body tissues e
of
insect & penetrate into
individual body cells
diffusion distance
↳ thin walls
short =
highly branched SA
-
gasentersleavestrachethoughpopnexokdetoncalledspiradeson
a
-
-respiratory gases in & out tracheal system in 3
ways
:
move
of
1. )longdifferingradient when cells respire oxygen used up A concentration towards ends of tracheoles
,
creates diffusion gradient to diguse to cells
from atmosphere
·
causing gaseous oxygen ,
CO2 produced by cells respiration in
dision gradient opposite direction causing gaseous CO2 to diffuse from cells to atmosphere
·
in
,
quicker digusion than water
↳
in air
Matt
traction trachea
2 enabling movements
muscles in insects mass in & out
of can
squeeze ,
of air
edu/water Fanaerobic respiration produces lactate (soluble t Doy muscle cells) ,
so water moves in
by osmosis
Spirade ·
water in ends
of
tracheoest in vol., drawing air into them so final diffusion pathway in
gas phase
trachea
↳
also leads to more water evaporation Though ,
trachees
musclegibre
Limiting Water Loss
-interrestrial organisms features that make good gas exchange system that water loss must balance without
same
I
compromising efficiency
increase
air at % saturated /water
gas exchange surface approx
IOO F
.
vapour evaporation of
less water
1. )
Small SA Vol . minimise
:
area over which water lost
is
2 ) Water
.
prod Coverings over Body Surfaces rigid I
outer skeleton of
chitin covered in waterproo cutide
.) Spiracles
3 be closed when at rest
I
can
, typically as needed
for
Oz
